Biomedical Frontiers, Inc. (BMF) has shown that non-toxic, macromolecular iron chelates can be produced by the covalent attachment of deferoxamine to biocompatible polymers and the subsequent addition of iron. Based on preliminary animal studies, these chelates show considerable promise as non-toxic contrast enhancing agents for use in magnetic resonance imaging. There is currently a profound need for a safe and efficacious contrast agent for the advancement of MR imaging of the gastrointestinal tract, the urinary system and the vascular system. The compounds being developed by BMF are excellent candidates for the improved utility and diagnostic capabilities of MRI in these tree areas. BMF proposes to synthesize and characterize a variety of these polymer-ferrioxamine derivatives, perform preclinical toxicology, and initiate clinical trials for safety and efficacy with one or more of these compounds. With the evolution of MRI as a primary modality in the radiologist's armentarium, a clear need has been demonstrated for agents that improve the diagnostic image. Initial studies indicate that the macromolecular chelates will be safe and efficacious contrast agents for specific MRI applications, and therefore will have significant commercial application.